Process and apparatus for finishing pressed fibrous articles



1934. G. J. MANSON 1,983,554

PROCESS AND APPARATUS FOR FINISHING PRESSED FIBROUS ARTICLES Filed Nov.22, 1928 I 25 25 z: JP l$\\\ 17 I i 17 M717)! 7 W Maxim/van PatentedDec. 11, 1934 raocass arm 1,sas,s s4 mm'rus roa FINISH- ING PBESSED.FIBROUB ARTICLES George James Manson, Hawkeabnry, Ontario,

Canada Application November 22, 1928, Serial No. 321,232

5 Claims. I (01. 92-54) This invention relates to improvements inprocess and apparatus for finishing pressed fibrousarticles and theobject of the invention is to provide an improved process and apparatusfor finish- I 5 ing pressed fibrous articles such as dishes. trays,-

food containers and the like and the object of the invention is toprovide an improved process and apparatus for finishing articles of thischaracter whereby a smooth surface free from drainage l markings may beproduced on one or more faces of the article and in .which the articlewill be ahfut discoloration or hydration of the fibrous The inventionconsists in the process and ap- 15 paratus all as hereinafter moreparticularly described and illustrated diagrammatically in theaccompanying drawing in which Figure 1 is a vertical" section through anap- ,paratus suitable for carrying out my.invention 20 illustrating onestep in the process.

Figure 2 is a vertical section of the apparatus illustrating a furtherstep.

In the drawing like characters of reference indicate corresponding partsin the different 25 views.

The apparatus comprises slower die 10 provided with a forming surface11, which surface is provided with drainage perforations 12 and beneaththese drainage perforations is a suction so chamber 13 and leading fromthis chamber 13 is a suction pipe 14. The-lower die 10 could besupported so that itmay be pressed with substantial pressure against theupper die in any suitable way such as by a hydraulic ram 15. Sur- 35rounding the lower die is a slidable guard 16 normaliy urged upwardly bysprings 17. 3

Cooperating with the lower die (see Fig. 1) is an upper die 18 which isprovided with a smooth forming surface 19 and which may be heated in 40any desired manner and in the form illustrated is shown provided with aheating chamber 20 to which may be lead any desired heating medium suchas steam, oil or the like. The forming surface of the lower die iscovered with a wire mesh 45 cloth 21.

In Fig. 2 an unheated upper die 22 having a smooth forming surfaceis-employed in cooperationtherewith. The lower die 23 is heated in anysuitable way similar to the upper die 18 in Fig. v1

50 and-as illustrated is shown provided with a heating chamber24. YApressed fibrous article being finished is illustrated by the numeral25.

- "Thepresentinvention relates only to the final as heating step in thefinishing ofpressed fibrous articles and preparatory to the introductionof the article 25 into the apparatus, as illustrated in Fig. 1, thearticle'would have been formed in any suitable apparatus so that it isin a relatively dry state.

This article is introduced into the dies as shown in Fig. 1 and 'ispressed therebetween with substantial pressure so that the heatedsurface 19 of the upper die 18 is pressed against the article withsubstantial pressure and at the same time this face 19 is heated to arelatively high temperature.

The face 19 of the upper die 18 thus constitutes a calendering memberwhich is'applied to the face of the article at relatively hightemperature and with substantial pressure and being smooth it produces asmooth surface on the face of the article pressed thereagainst, whichface will be entirely free from drainage markings.

At the completion of the step illustrated in Fig. l I have produced anarticle which has a smooth surface on one face thereof, which surface isentirely free from drainage markings. In this step any steam or vaporwhich is produced may freely escape through the drainage perforations 12in the lower die and is carried off through the suc- .both sides of thearticle a further step, illustrated in Fig. 2, is employed. In this casethe I lower die 23 has a smooth forming surface which is heated to arelatively high temperature and this smooth heated surface is appliedwith substantial pressure against the article and thus constitutes acalendering member which is heated to 5 a relatively high temperatureand which is applied with substantial pressure to the face of thearticle, with the result that a smooth surface free from drainagemarkings is produced on the face of the article presented to the lowerdie. 40

In this step the upper die 22 also has a smooth face, and due to thefact that the article is pressed between two smooth faces it willprobably be necessary to provide, some suitable means for permitting theescape of any vapour formed and this may be done by suitably arrangingfor a vibratory motion of the ram 15 so that the pressure between thedies may be applied intermittently and thus permit the escape of vapourfrom betweenthe die surfaces.

While I have shown and'described the dies 18 and 22 as provided withheating chambers to which may be fed a heating medium, my invention isnot limited to any particular manner of heating as this may beaccomplished in any suitable manner. I

From the foregoing it will be apparent that I have devised a novelprocess and apparatus for finishing pressed fibrous articles whereby theobjects of my invention have been attained.

Various modifications may be made in my invention without departing fromthe spirit thereof dry, wet molded, pressed, fibrous articleto acalendering operation at relatively high temperature and substantialpressure and exhausting by suction the vapor generated in saidoperation, then subjecting the article to a further calenderingoperation-between smooth faced dies.

2. The herein described method which comprises subjecting a preformedthin and partially dry, wet molded, pressed fibrous article to acalenderlng operation at relatively high temperature and substantialpressure and exhausting by suction the vapor generated insaid operation,

' then subjecting the article to a further calendering operation withheat and pressure betwee smooth faced dies. 7

3. Apparatus for finishing a .preformed thin and partially dry, wetmolded, pressed fibrous- 1, 9ss,e54 a article, comprising a smooth facedcalendering 1 member, means for heating said calendering member, meansfor applying said heated calendering member with substantial pressure tothe surface of the article, suction means communicating with the articleduring said calendering operation, and means for subjecting the articleto a further calendering operation between smooth faced dies.

4. Apparatus for finishing a preformed thin and partially dry, wetmolded, pressed, fibrous article, comprising av smooth faced calenderingmember, means for heating said calendering member, means for applyingsaid heated calendering member with substantial pressure to the surfaceof the article, suction means communicatingwith the article during saidcalendering operation, and means for subjecting the article to a furthercalendering operation with heat and pressure between smooth faced dies.

5. The herein described method which comprises subjecting a thinpreformed and partially dry, wet molded, pressed, fibrous article toacalendering operation at a relatively high tem--- perature andsubstantial pressure to calender one surface thereof, and exhausting 'bysuction the vapor generated in said operation, then subjecting thearticle to a further calendering op-' eration by applying a heatedsmooth faced die to the uncalendered surface, and a smooth facedunheated die to the calendered surface, and sub"- 4 jecting the articleto substantial pressure while vibrating the dies to permit escape of thevapor generated. GEORGE JAMES MANSON.

